Title:
MATHEMATICS TEACHING TOOL
United States Patent 3455034


Inventors:
Schott, Andrew F.
Application Number:
US3455034DA
Publication Date:
07/15/1969
Filing Date:
10/19/1965
Assignee:
Andrew, Schott F.
Primary Class:
International Classes:
G09B19/02; (IPC1-7): G06C1/00
View Patent Images:
US Patent References:
3151404Abacus1964-10-06
2646631Combined abacus and counting rack1953-07-28
0826732N/A1906-07-24
0232482N/A1880-09-21